Closure with pressure compensating valve for a liquid container

ABSTRACT

The closure has a bung-type socket (10) of elastic material which fits sealingly into the filling hole and is provided with a central orifice (18). The valve element (20) of the pressure-compensating valve occupies in the central orifice a clearly defined closed position and a clearly defined pressure-compensating position, between which it can be turned within limits defined by stops. The bung-type socket (10) has a lateral pressure-compensating duct (42), the outside end of which is disposed above the liquid level in the completely filled container. The valve element (20) in pressure-compensating position opens up a flow path from the inside end of the pressure-compensating duct (42) to the upper side of the bung-type socket (10), while in closed position it shuts off the path on the inside, covers it on the outside and seals it tightly on both inside and outside.

BACKGROUND OF THE INVENTION

The invention relates to a closure with pressure-compensating valve forthe filling hole of a liquid container, with a bung-type socket ofelastic material which fits sealingly into the filling hole and isprovided with a central orifice, and with a valve element which can bemanually turned into position and which occupies in the central orificea sealing closed position and a pressure-compensating position, in whichthe interior of the container is in communication with the atmosphere.

Such a closure is known from German Patent DE 4219571 C2. It has abung-type socket with alternately larger and smaller axial ventilationgrooves along the wall of the central orifice and a valve element withalternately larger and smaller axial ventilation fins along the outsidesurface. The valve element has closed positions, in which matchinggrooves and fins are in engagement, and pressure-compensating positions,in which non-matching grooves and fins are in engagement.

When the liquid container is completely filled, the bungtype socket dipswith its lower end into the liquid. Actuation of thepressure-compensating valve then has the consequence that liquid emergesfrom the container. A further disadvantage is that it is difficult todistinguish whether the valve element of the pressure-compensating valveis in one of the plurality of possible closed positions orpressure-compensating positions.

SUMMARY OF THE INVENTION

The object of the invention is to provide a satisfactorily hygienic,simply and safely operable closure of the type cited in theintroduction, which is capable of achieving pressure compensation whenthe container is completely full.

This object is achieved with such a closure by the fact that thebung-type socket has a lateral pressure-compensating duct, the outsideend of which is disposed above the liquid level in the completely filledcontainer, that the valve element can be turned within limits defined bystops from a clearly defined closed position to a clearly definedpressure-compensating position and back, and that the valve element inpressure-compensating position opens up a flow path from the inside endof the pressure-compensating duct to the upper side of the bung-typesocket, while in closed position it shuts off the path on the inside,covers it on the outside and seals it tightly on both inside andoutside.

The clear definition of a closed position and pressure-compensatingposition and the action of turning the valve element therebetween withinlimits defined by stops make the closure according to the invention verysafe to operate. The positions can be clearly marked, and it is apparentat any time whether the valve element is in closed position orpressure-compensating position. The outside cover and seal of thepressure-compensating flow path when the valve element is in closedposition ensure that no residual liquid or rinse liquid can enter theclosure during the filling process. The closure therefore satisfies themost stringent hygiene requirements.

In one preferred embodiment, the valve element has an external flange,which fits into a recess of the bung-type socket.

On the bottom of the recess there is provided a groove extending outwardfrom the central orifice. The valve element has a surface groove, whichin pressure-compensating position brings the inside end of thepressure-compensating duct into communication with the groove on thebottom of the recess.

In another preferred embodiment, the flange of the valve element isnoncircular. In closed position and pressure-compensating position itsnaps radially onto the outside of the bung-type socket with aprojection. In closed position the projection covers the outside end ofthe groove on the bottom of the recess.

In another preferred embodiment, the valve element is notched over thecircumference. The bung-type socket is provided with a cog, whichlocates the notch and becomes stopped at the ends thereof, therebylimiting the adjustment angle of the valve element and defining theclosed position and pressure-compensating position.

In another preferred embodiment, the portion of the valve elementdisposed opposite the inside end of the pressure-compensating duct formsin circumferential direction a ramp, which descends in turning directionfrom closed position to pressure-compensating position. By virtue ofthis ramp, the initial bias exerted by the seal against the inside endof the pressure-compensating duct is gradually relaxed when the valveelement is turned from closed position to pressure-compensatingposition. This opens up the possibility of smooth, gradual pressurecompensation and in particular careful pressure relief, for examplebefore beer is tapped for the first time.

In another preferred embodiment, the closure has anoriginality-protecting feature, which reveals whether or not thepressure-compensating valve has already been actuated.

In another preferred embodiment, the valve element is provided with aliftable curved handle, which is fastened to the valve element by meansof ribs, which break away when the handle is lifted for the first time.

In another preferred embodiment, the curved handle attached to the ribsis flush-mounted in the recess of the bung-type socket. The curvedhandle is therefore protected from inadvertent actuation, andstackability of the containers is ensured.

In another preferred embodiment, the recess of the bung-type socket hasa widened portion, which allows the curved handle to be grasped fromunderneath.

In another preferred embodiment, the bung-type socket is made in thetwo-plastic technique from a soft external part and a hard reinforcingring completely embedded therein.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be explained in more detail hereinafter by referenceto a practical example illustrated in the drawing, wherein:

FIG. 1 shows the side view of the valve element of a closure withpressure-compensating valve;

FIG. 2 shows a horizontal projection from above of the valve elementseen in direction II of FIG. 1;

FIG. 3 shows a horizontal projection from below of the valve elementseen in direction III of FIG. 1;

FIG. 4 shows the cross-sectional view through the diameter of abung-type socket belonging to the closure;

FIG. 5 shows a horizontal projection from above of the bung-type socketseen in direction IV of FIG. 4; and

FIG. 6 shows in horizontal projection from above an assembly drawing ofbung-type socket and valve element.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The closure described hereinafter functions to close tightly the fillinghole of a liquid container. Examples of such containers are kegs,mini-kegs (party kegs) or cans, from which liquids, especiallybeverages, can be drawn without pressure or under pressure. It is usablein particular for party kegs beer.

The filling hole of such containers is a round hole, which is upwardlyopen during the filling process. The closure contains a bung-type socket10 of elastic material, which on the outside is substantiallyrotationally symmetric relative to its central axis and which has anoutwardly protruding flange 12, with which it bears against the outsidewall of the container. Bung-type socket 10 projects with a substantiallyconical tapering portion 14 into the container. The generating line oftapering portion 14 is sigmoidally curved. Between flange 12 andtapering portion 14 the diameter of bung-type socket 10 is recessed toform an annular groove 16, into which the rim of the filling hole fitssealingly when bung-type socket 10 is forced into place.

To dispense liquid, the container has a lower dispensing orificeseparate from the filling hole. This can be a bunghole, which is tappedwith a tapping fitting or similar device, or a spigot integrated intothe container.

Vibrations during transportation and/or warming can cause in beer kegsbuild-up of considerable overpressure, with the result that almostexclusively foam is tapped at first. It is recommended that thisoverpressure be carefully relieved before tapping for the first time.For this purpose the bung-type socket is equipped with a manuallyoperated pressure-compensating valve.

When liquid is dispensed from the lower dispensing orifice withoutpressure, a partial vacuum is produced above the liquid level in thecontainer. To break this partial vacuum, air can be admitted to thecontainer via the pressure-compensating valve.

Bung-type socket 10 has a central orifice 18, in which valve element 20of the pressure-compensating valve is seated. Valve element 20 isaccessible from the outside to allow valve operation. In central orifice18 of bung-type socket 10 it optionally occupies a sealing closedposition or a pressure-compensating position, in which the interior ofthe container above the liquid level therein is in communication withthe atmosphere.

Central orifice 18 of bung-type socket 10 is an inwardly tapering blindhole of basically conical shape, which is not completely axiallysymmetric but has both conical surface portions 22, 24, 26 and plaincylindrical surface portions 28, 30 distributed over circumference anddepth. Valve 20, which is of substantially complementary geometry,thereby has a well-defined mounting position in central orifice 18.

Flange 12 of bung-type socket 10 has on the outside a substantiallyplain cylindrical recess 32 of large diameter and therebehind, towardthe interior of central orifice 18, an annular bead 34, which protrudesradially inward beyond conical surface 22 of central orifice 18. Theblind hole ends at the inside in a throat 38 defined by annular bead 36and a plain cylindrical section 40 of larger diameter.

At surface 28 of the blind hole there extends a pressure-compensatingduct 42 in the form of a radial bore, which passes transversely throughbung-type socket 10 at approximately half height. Once bung-type socket10 has been forced into place, the radial bore is disposed above theliquid level in the completely filled container.

Valve element 20 has on the outside a flange 44 which fits into recess32 of bung-type socket 10. To this there is adjoined on the inside asealing portion 46 of smaller diameter, into which outer annular bead 34of bung-type socket 10 snaps. Valve element 20 tapers inwardly withconical surface portions 48, 50, 52 and plain cylindrical surfaceportions 54, 56 to a neck 58, and ends in a plain cylindrical head 60 oflarger diameter. Inner annular bead 36 of bung-type socket 10 snaps intoplace against neck 58.

Valve element 20 has on the outside surface a notch 62 extending for 90°in circumferential direction. Bung-type socket 10 has on the insidesurface a cog 64, which projects into notch 62 and acts as a stoplimiting the angle through which valve element 20 can be turned.

The portion of valve element 20 disposed opposite the inside end ofpressure-compensating duct 42 forms in circumferential direction a ramp,which descends in the turning direction from closed position topressure-compensating position.

Valve element 20 has an axial surface groove 65, which extends from theheight of the inside end of pressure-compensating duct 42 to theunderside of flange 44.

On the bottom of recess 32 of the bung-type socket there is provided agroove 66, which is disposed in the same diametral plane aspressure-compensating duct 42 and which extends from central orifice 18of bung-type socket 10 to the outside rim of recess 32.

Flange 44 of valve element 20 is noncircular. It has a radiallyprojecting nose 68, which fits into two bulges 70, 72 of recess 32 ofthe bung-type socket. Thereby the sealing closed position and thepressure-compensating position of valve element 20 are marked and fixedby snap-in effect. Groove 66 on the bottom of recess 32 of the bung-typesocket ends in bulge 72 corresponding to pressure-compensating position.

In pressure-compensating position, a flow path between the interior ofthe container and the atmosphere is opened up via pressure-compensatingduct 42, surface groove 65 and groove 66 on the bottom of recess 32. Inclosed position, the outside end of groove 66 is covered and tightlyclosed by nose 68 on flange 44 of valve element 20.

From flange 44 of valve element 20, and extending over half thecircumference thereof, there is branched off a curved handle 74, whichcan be lifted by pivoting around a diametral axis 76. Curved handle 74is fastened to valve element 20 with ribs 78, which break off when thehandle is lifted for the first time and form clearly visible fracturefaces. Thereby originality protection is achieved.

Curved handle 74 is flush-mounted in recess 32 of the bung-type socket.Recess 32 has a widened portion 80, which extends to the rim ofbung-type socket 10 and in which there is disposed a prolongation 82 ofthe curved handle, which prolongation projects outwardly from flange 44and can be grasped from underneath at the rim.

While curved handle 74 is lifted, valve element 20 can be turned fromclosed position to pressure-compensating position and back.

What is claimed is:
 1. A closure with pressure-compensating valve forthe filling hole of a liquid container, with a bung-type socket ofelastic material which fits sealingly into the filling hole and isprovided with a central orifice, and with a valve element which can bemanually turned into position and which occupies in the central orificea sealing closed position and a pressure-compensating position, in whichthe interior of the container is in communication with the atmosphere,characterized in that the bung-type socket (10) has a lateralpressure-compensating duct (42), the outside end of which is disposedabove the liquid level in the completely filled container, in that thevalve element (20) can be turned within limits defined by stops from aclearly defined closed position to a clearly definedpressure-compensating position and back, and in that the valve element(20) in pressure-compensating position opens up a flow path from theinside end of the pressure-compensating duct (42) to the upper side ofthe bung-type socket (10), while in closed position it shuts off thepath on the inside, covers it on the outside and seals it tightly onboth inside and outside.
 2. A closure according to claim 1,characterized in that the valve element (20) has an external flange (44)which fits into a recess (32) of the bung-type socket (10), in that onthe bottom of the recess (32) there is provided a groove (66) extendingoutward from the central orifice (18), and in that the valve element(20) has a surface groove (65), which in pressure-compensating positionbrings the inside end of the pressure-compensating duct (42) intocommunication with the groove (44) on the bottom of the recess (32). 3.A closure according to claim 1, characterized in that the flange (44) isnoncircular and in closed position and pressure-compensating position itsnaps radially onto the outside of the bung-type socket (10) with aprojection (68), and in that in closed position the projection (68)covers the outside end of the groove (66) on the bottom of the recess(32).
 4. A closure according to claim 1, characterized in that the valveelement (20) is notched over the circumference, and in that thebung-type socket (10) is provided with a cog (64), which locates thenotch (62) and becomes stopped at the ends thereof, thereby limiting theadjustment angle of the valve element (20) and defining the closedposition and pressure-compensating position.
 5. A closure according toclaim 1, characterized in that the portion of the valve element (20)disposed opposite the inside end of the pressure-compensating duct (42)forms in circumferential direction a ramp, which descends in turningdirection from closed position to pressure-compensating position.
 6. Aclosure according to claim 1, characterized in that it has anoriginality-protecting feature, which reveals whether or not thepressure-compensating valve has already been actuated.
 7. A closureaccording to claim 1, characterized in that the valve element (20) isprovided with a liftable curved handle (74), which is fastened to thevalve element (20) by means of ribs (78), which break away when thehandle is lifted for the first time.
 8. A closure according to claim 1,characterized in that the curved handle (74) attached to the ribs isflush-mounted in the recess (32) of the bung-type socket (10).
 9. Aclosure according to claim 1, characterized in that the recess (32) ofthe plug has a widened portion (80), which allows the curved handle (74)to be grasped from underneath.
 10. A closure according to claim 1,characterized in that the bung-type socket (10) is made in thetwo-plastic technique from a soft external part and a hard reinforcingring completely embedded therein.